Records of the effects of inbreeding in humans

In the episode on the development of rail transport, ("Fuel to the Flame," episode 6) James Burke mentions in passing that "the railroad changed society genetically" because people began to marry outside their villages. Documenting that claim requires a bit of digging through chronicled events of the 18th and 19th centuries. Often such problems of inbreeding are buried in works devoted to other topics and sometimes they are there only to add certain nuances to the mood. By his statement, Burke gives the impression that once people started to travel and to intermarry between villages, the genetic change was abrupt. But there were many villages in England with a relatively static genetic stock well into the 19th century. Even today many villages are inhabited by the same families who settled there centuries ago. Here are two comments on the possible effects of inbreeding. The first is a description of some genetic disorders in one English village in the latter part of the 19th century. It is taken from Further Chronicles of Fairacre, by Miss Read (Mrs. Dora Saint):

Miss Clare Remembers

Looking back later, to those early days at Beech Green, Miss Clare was amazed to think how many subnormal and eccentric people there were among that small number in those late Victorian days. There were many reasons. Inbreeding was a common cause, for lack of transport meant that the boys and girls of the village tended to marry each other, and the few families there became intricately related. Lack of skilled medical attention, particularly during childbirth, accounted for some deformities of mind and body, and the dread of mental hospitals - sadly justified in many cases - kept others from seeking help with their problems. Certainly, when Dolly first went to live at Beech Green, there were half a dozen souls in the neighborhood who were as much in need of attention as poor Mabel.

There was the boy who had epileptic fits, who sat in the desk next to Ada, and was looked upon with more affection than distress by his classmates, as the means of enlivening Mr Finch's boring lessons. There was old Mrs Marble, who gibbered and shook her fist at the children from the broken window of her filthy cottage near the school, and who would certainly have been ducked in the horsepond had she had the misfortune to have been born a century earlier. There was a very nasty man who delighted in walking about the woods and lanes with his trousers over his arm, frightening the women and little girls out of their wits, but excused by the men as 'only happening when the moon was at the full, poor fellow'.

Then there were the three White children, abysmally slow at lessons, but with tempers of such uncontrollable violence that the whole school went in terror of them. How much of this vicious frenzy was due to mental disorder, and how much to their parents' treatment of it, was debatable. It was the custom of Mr and Mrs White to lock their refractory offspring in a cupboard under the stairs where, in the smelly darkness among the old shoes and coats that hung there, they were allowed to scream, sob, fight, pummel the door, and exhaust their hysteria before being let out again, some hours later, white and wild-eyed and ready to fall into their nightmare-haunted beds.

Even the great ones of the village had their sufferings. The lady of the manor, Mrs Evans, whose visits to the school meant much curtseying and bobbing, had one frail chick among her six sturdy ones, and Miss Lilian was never seen without a maid or her governess in attendance ready to direct her charge's wan look towards anything of cheer.

As young Dolly soon discovered, Beech Green had its darker side, the reverse of the bright flower-decked face which charmed the newcomers. But it all added to the excitement of daily living. It gave the solemn little girl a chance to observe human frailties and quirks of behavior, and gave her too an insight into the courage and good humor with which her fellows faced personal tragedy.

These early lessons were to stand her in good stead, for before long she too would be involved in a family disaster whose repercussions were to echo down many years of her adult life.

In welcoming all that life in Beech Green offered her, in both happiness and horror, the child unwittingly prepared herself for the testing time which lay ahead.

The second is from Thomas Jefferson on Democracy and is taken from a letter by him to H. Langdon in 1810. Notice that Jefferson is a bit ambiguous as to the cause of madness of Kings. Does he think it the result of heredity (Marriages only within royal families) or environment (idleness, pampering and banishing "whatever might lead them to think")? Remember, it would be another 55 years before Gregor Mendel published his laws of genetics and it would be a while after that before people realized that humans follow the same genetic laws as do other animals:

European monarchs--fools and madmen. To J. Langdon, 1810

The practice of Kings marrying only in the families of Kings, has been that of Europe for some centuries. Now, take any race of animals, confine them in idleness and inaction, whether in a stye, a stable or a stateroom, pamper them with high diet, gratify all their sexual appetites, immerse them in sensualities, nourish their passions, let everything bend before them, and banish whatever might lead them to think, and in a few generations they become all body and no mind . . . Such is the regimen in raising Kings, and in this way they have gone on for centuries.

While in Europe, I often amused myself with contemplating the characters of the then reigning sovereigns . . . Louis XVI was a fool, of my own knowledge . . . The King of Spain [Charles IV] was a fool, and of Naples [Ferdinand IV] the same. They passed their lives in hunting, and despatch two couriers a week, one thousand miles, to let each other know what game they had killed the preceding days. The King of Sardinia [Victor Amadeus III] was a fool. All these were Bourbons. The queen of Portugal [the Mad Maria], a Braganza, was an idiot by nature. And so was the King of Denmark [Christian VII]. Their sons, as regents, exercised the powers of government. The King of Prussia [Frederick William II], successor to the great Frederick, was a mere hog in body as well as in mind. Gustavus [III] of Sweden, and Joseph [II] of Austria, were really crazy, and George [III] of England, you know, was in a straight waistcoat (straight jacket -- O.S.). There remained, then, none but old Catharine, who had been too lately picked up to have lost her common sense.... These animals had become without mind and powerless; and so will every hereditary monarch be after a few generations. . . . And so endeth the book of Kings, from all of whom the Lord deliver us.